Construction and maintenance of airport runways has become a critical consideration for airport design, in terms of aircraft safety and passenger comfort during take-off, landing and taxiing.
Stringent specifications, necessitated by larger and more heavily loaded aircraft, require runway construction to a surface tolerance of maximum 5 mm deviation from a 4.5 m long straight-edge.
To maintain a runway in working condition, the profile of the runway must be measured regularly. This profile is a set of points taken along the runway that describe relative elevation. National aviation authorities generally have profile standards which must be met.
The previous methods of determining the profile of a runway were laborious. These methods included: surveying with transits, measuring with a straight edge, and measuring with a level.
There are a number of problems with the previous methods. First, the measurements take an inordinate amount of time to complete. To manage this time effectively, the actual measurement phase is often minimized, with mathematical interpolation approximations used to fill in data points. Second, it takes a long time to analyze and use these data points. The difficulties inherent in the prior methods means that such tasks have sometimes been completed less frequently than might otherwise have been the case.